Our invention relates to water-soluble polyvinyl alcohol or partially hydrolyzed polyvinyl acetate having admixed therewith compatible fragrances particularly for use in fabrication of toilet rim blocks.
Accordingly, a need exists for a high compatible fragrance loading of polyvinyl alcohol or partially hydrolyzed polyvinyl acetate whereby an effective air freshening device can be fabricated in a commercially feasible manner.
U.S. Pat. No. 4,911,858 issued on Mar. 27, 1990 discloses solid cake lavatory cleansing block composition comprising polyethylene glycol polymer and guar gum, and optional ingredients which include fragrances, dyes, solid binders, filler material and mixtures thereof.
U.S. Pat. No. 4,820,449 issued on Apr. 11, 1989 discloses a cleaning block for the tank of flush toilets comprising: 10 to 30% by weight of monoalkyl sulfate, sodium salt, 5 to 40% by weight of fatty acid alkanolamide, and 15 to 60% by weight of a water-soluble inorganic alkali salt, and optionally calcium-complexing carboxylic acids or alkali salts thereof, perfume, dye and other auxiliaries.
U.S. Pat. No. 4,722,802 issued on Feb. 2, 1988 discloses a surfactant cleansing block suitable for placement in a toilet tank or other water-containing reservoir, comprising a hydrated cellulosic binder and a surfactant, and processes for making same, especially by extrusion of a homogeneous blend of said blender and said surfactant.
Toilet rim blocks, however, have never been fabricated using polyvinyl alcohol or partially hydrolyzed polyvinyl acetate with the advantage obtained when using such polymers.
Extruded polyvinyl alcohol when used with other polymers is shown to be useful, for example, in chewing gum containing compositions for control release of flavor bearing substances in U.S. Pat. No. 5,116,627 issued on May 26, 1992.
U.S. Pat. No. 5,116,627 issued on May 26, 1992 describes a chewing gum comprising a chewing gum base having dispersed therein, separately, a multiplicity of sweetener bearing polymeric particles and/or flavor-bearing polymeric particles, said polymeric particles further comprising:
(a) at least one water-soluble normally solid polymer (for example, polyvinyl alcohol, extruded); PA1 (b) at least one water-insoluble normally solid polymer; PA1 (c) and either: PA1 (a) adding sufficient energy to the polyvinyl alcohol to both melted and essentially eliminate the crystallinity in the melt; and PA1 (b) simultaneously removing energy from the melt at a rate sufficient to avoid decomposition of the polyvinyl alcohol and PA1 (a) extruded polyvinyl alcohol or partially hydrolyzed polyvinyl acetate with the maximum mole ratio of the acetyl moiety:hydroxyl moiety being about 3:1, having a number average molecular weight of from about 15,000 up to about 68,000 containing from 0 up to about 13% by weight of a polar plasticizer; PA1 (b) from about 1 up to about 20% by weight of a compatible fragrance contained within the polyvinyl alcohol or the partially hydrolyzed polyvinyl acetate; PA1 (c) from 0 up to about 20% by weight of a "foaming agent" which is a first surfactant and which can be a detergent, contained within the polyvinyl alcohol or partially hydrolyzed polyvinyl acetate; PA1 (d) from 0 up to about 20% by weight of hydrophobic silica contained within the polyvinyl alcohol or the partially hydrolyzed polyvinyl acetate; PA1 (e) from 0 up to about 20% by weight of at least one second surfactant in addition to the aforementioned "foaming agent" of (c); PA1 (f) from 0 up to about 5% of a water-soluble dye; and PA1 (g) from 0 up to about 4% of a "foam booster". PA1 glycerine; PA1 triethanolamine; PA1 ethylene glycol; PA1 propylene glycol; PA1 diethylene glycol; PA1 dipropylene glycol; PA1 diethanolamine; and PA1 methyldiethylamine. PA1 STANDAPOL.RTM. 7023 (an anhydrous blend of Cocamide DEA and DEA-Myreth Sulfate detergent); PA1 WITCONATE.RTM. AOK (manufactured by Witco Chemical Comapany (solid anionic alpha sulfonate)); and PA1 WITCONATE.RTM. 90 FLAKE (manufactured by Witco Chemical Company (solid anionic alpha sulfonate)). PA1 PLURONIC.RTM.F88 (a block copolymer of ethylene oxide and propylene oxide manufactured by BASF); PA1 PLURONIC.RTM. F77 (a block copolymer of ethylene oxide and propylene oxide manufactured by BASF); and PA1 WITCONATE.RTM. 90. PA1 INCROMIDE.RTM. CA (Cocamide DEA) manufactured by Croda, Inc. PA1 1. The Krauss-Maffei twin screw extruder manufactured by the Krauss-Maffei Corporation/Extruder Division, 3629 West 30th Street, Wichita, Kans. 67277; PA1 3. The Leistritz Twin Screw Dispersion Compounder manufactured by the American Leistritz Extruder Corporation, 198 U.S. Route 206 South, Sommerville, N.J. 08876; PA1 4. The ZSK Twin Screw Co-Rotating Extruder manufactured by the Werner & Pfeiderer Corporation, 663 East Crescent Avenue, Ramsey, N.J. 07446; PA1 5. The MPC/V Baker Perkins Twin Screw Extruder manufactured by the Baker Perkins Inc. Chemical Machinery Division, Saginaw, Mich. 48601; PA1 5. The Berstorff twin screw or foam extrusion equipment manufactured by Berstorff Corporation, P. O. Box 240357, 8200-A Arrowridge Boulevard, Charlotte, N.C. 28224; and PA1 6. The Theysohn TSK Co-Rotating Extruder manufactured by the Theysohn Corporation of 2 Corporate Drive, Suite F, Radford, Va. 24141.
(i) at least one flavor composition a substantial portion of which is incorporated in the water-insoluble polymer and a substantially portion of which is incorporated in the water-soluble polymer; and/or PA2 (ii) at least one sweetener composition a substantial portion of which is incorporated in the water-insoluble polymer and a substantial portion of which is incorporated in the water-soluble polymer;
the water-soluble polymer and the water-insoluble polymer being physically associated with each other associated in such a manner that one is in the form of a multiplicity of discrete entities in a matrix of the other.
Holzner, U.S. Pat. No. 4,803,195 issued on Feb. 7, 1989 describes a personal care composition having deodorant or antiperspirant activity and containing, in addition to an active deodorant or perspirant base, a perfuming base, either in the form of an aqueous emulsion, or in micro-encapsulated form. the perfume base is combined with a film-forming substrate such as polyvinyl alcohol and an emulsifying agent. It is stated in U.S. Pat. No. 4,803,195 that the composition of the invention has the advantage of releasing the volatile constituents of the perfume at the appropriate moment by the action of a source of moisture, in particular, sweat.
Hussain and Zukoski in U.S. Pat. No. 4,552,693 issued on Nov. 12, 1985 describes transparent fragrance-emitting articles, formed from a composition which has a relatively low set point and comprises a thermoplastic polyamide resin plasticizer system. The plasticizer system comprises a sulfonamide and mineral oil which have been titrated to clarity with a solvent for both the oil and sulfonamide. U.S. Pat. No. 4,552,693 does not, however, contemplate water-soluble thermoplastic polymers such as polyvinyl alcohol in the absence of other organic polymers but in the presence of a plasticizer.
Whyte, U.S. Pat. No. 4,339,356 issued on Jul. 13, 1982 describes heavily perfumed detergent compositions having both immediate and long lasting perfume emitting properties prepared by a process in which perfume is emulsified in a water solution of a water-soluble polymer such as polyvinyl alcohol and the emulsion is mixed with a powdered hydratable material in such a ratio that all of the water in the emulsion can be bound in the resulting hydrate eliminating a separate drying step. In U.S. Pat. No. 4,339,356, the result is a dry free flowing granular material which can be readily dry mixed into fully formulated detergent compositions. It is further indicated that the perfume is retained in the polymeric matrix and is released at the point of product use when contacted with water. U.S. Pat. No. 4,339,356 does not contemplate, however, a toilet rim block containing extruded polyvinyl alcohol and a relatively high loading of fragrance.
Rutherford, U.S. Pat. No. 4,842,761 issued on Jun. 27, 1989 discloses laundering compositions containing particulate olfactory polymers which provide for the controlled release of olfactory compositions such as perfumes, where the particulate olfactory polymers comprising a water-soluble normally solid polymer (for example, polyvinyl alcohol), a water-insoluble normally polymer, and at least one olfactory composition which is in each polymer, one polymer being in the form of discrete entities in a matrix of the other polymer, together with laundering articles such as packets containing such compositions. It is indicated by Rutherford that the composition can be formed by means of extrusion (attention is drawn to FIG. 2E) but the extrusion involves extrusion of both the water-soluble and water-insoluble polymers simultaneously. Reference is specifically made to column 11, lines 11-36 of U.S. Pat. No. 4,842,761.
Marten, U.S. Pat. No. 5,051,222 issued on Sep. 24, 1991 discloses methods for producing the polyvinyl alcohol and partially hydrolyzed polyvinyl acetate useful in our invention. Marten, et al, U.S. Pat. No. 5,051,222 discloses a method for extruding polyvinyl alcohol which includes:
rapidly cooling the extruded melt, reducing the heat history and improving the resulting color of the extrudable polyvinyl alcohol. U.S. Pat. No. 5,051,222 is incorporated herein by reference. U.S. Pat. No. 5,051,222 discloses the creation of polyvinyl alcohol and partially hydrolyzed polyvinyl acetate wherein the maximum mole ratio of acetyl-hydroxyl moieties is about 1:4 having a number average molecular weight of from about 15,000 up to about 68,000 and containing a plasticizer. Of specific interest is Example I at column 10, lines 7-60 of U.S. Pat. No. 5,051,222.
Grubb, U.S. Pat. No. 3,725,311 issued on Apr. 3, 1973 discloses an extrudable composition and process for producing it comprising a polymer of 80 to 90% polyvinyl chloride, 2 to 20% polyvinyl acetate and 0 to 20% polyvinyl alcohol, a plasticizer, a filler to maintain a dry mixture and a volatile odor-neutralizing or modifying agent (such as a perfume). The Grubb reference U.S. Pat. No. 3,725,311 states that the composition is extrudable at a temperature of below 250.degree. F. in order to avoid loss of the volatile odor-neutralizing agent through degradation or evaporation. The Grubb copolymer is not, however, water soluble and cannot properly be used in a toilet rim block as in the case of the above-identified Application.
Procter & Gamble, European Published Patent Application No. 583,512 filed on Aug. 18, 1992 discloses a detergent additive comprising a mixture of (a) a water-soluble or water-dispersible detergent active compound and (b) a surfactant absorbed into (c) a porous hydrophobic material which is coated with (d) a hydrophobic coating material. The porous hydrophobic material can be, for example, silica. The polymeric material may be, for example, polyvinyl alcohol. Water-soluble toilet rim blocks, however, made from polyvinyl alcohol or partially hydrolyzed polyvinyl acetate having a number average molecular weight of from about 15,000 up to about 68,000 are not contemplated by the Procter & Gamble European Application.
Published European Application No. 380,103 (Dow Corning) filed on Jan. 25, 1990 discloses a polyvinyl alcohol hydrogel dispenser for controlled release of fragrances and the like. Extruded polyvinyl alcohol or partially hydrolyzed polyvinyl acetate containing a high loading of fragrance for use in fabricating toilet rim blocks is not, however, contemplated by the Dow Corning Published European Application.
L'Oreal Japanese Published Application No. J94/010,128 (corresponding to U.K. Patent Specification No. 2,190,393 filed on Sep. 2, 1994) discloses the use of partially acetylated polyvinyl alcohol as a foaming agent in an aqueous aerosol foam composition for treating skin or hair. Foaming agents in combination with polyvinyl alcohol or partially hydrolyzed polyvinyl acetate for use in fabricating toilet rim blocks are now, however, contemplated by the L'Oreal disclosure.
In summary, nothing in the prior art contemplates the composition of matter or the process for producing same or the toilet rim block of our invention.